Ventriculo-atrial shunt



1970 E. M. FOUNTAIN 3,492,996

VENTRICULO-ATRIAL SHUNT Filed Feb. 9, 1966 2 Sheets-Sheet lTEZFJCUPfl/VG JECT/O/V awn/a1? Vf/VA ('14 V4 ATE/AL AL L Am/AL WEJ070170 M Faun av/7 INVENTOR.

BY Mam Feb. 3, 1970 E. M. FOUNTAIN 3,492,996

VENTRICULO-ATRIAL SHUNT Filed Feb. 9, 1966 I 2 Sheets-Sheet 2 504 /0/70l7. fbwrfa/n INVENTOR.

United States Patent 3,492,996 VENTRICULO-ATRIAL SHUNT Edmund M.Fountain, Houston, Tex., assignor to Dow Corning Corporation, Midland,Mich., a corporation of Michigan Filed Feb. 9, 1966, Ser. No. 526,294Int. Cl. A61m 27/00 US. Cl. 128-350 Claims ABSTRACT OF THE DISCLOSUREThis application describes a surgically implantable device for relievingfluid pressure on the brain. The device comprises a ventricular conduitadapted for introduction into the brain, a pumping device attached tothe ventricular conduit and an outlet conduit attached to the pumpingdevice and adapted to be inserted into the atrium. The pumping device isa substantially flat, flexible plate adapted to overlie the skull andhas a pair of bubble-shaped chambers positioned thereon and adapted forfinger manipulation to provide pumping action to clear the conduits ofobstructions. The outlet end of the device is provided with flexiblewings adapted to hold the device within the atrium or center it in thevein entering the atrium in the event that the end is pulled from theatrium. Oneway valves are provided to prevent blood back-flow into thebrain.

This invention concerns a new and improved device for treatinghydrocephalics, i.e., those persons, usually infants or children beingafflicted with, as commonly described, water on the brain. Also, thiscondition may exist in certain adults whose circulation or absorption ofcerebro-spinal fluid is impaired by various inflammatory or tumorprocesses.

More particularly this invention contemplates a means whereby secretedcerebro-spinal fluid may be directed into the blood stream and therebythroughout the normal course of the body system.

Normally, cerebro-spinal fluid is secreted by the choroid plexus andventricular lining within the cranial ventricles. Such fluid may enterthe vascular system by a route pproximated by passing out of the lateralventricles, through the third ventricle, out the formaina of Magendieand Lushka, into the cisterna magna whenceforth into the subarrachnoidspaces and absorbed by the blood system. Such fluids may be absorbed andrecycled several times daily.

With hydro-cephalics'the cerebro-spinal fluid is unable to be absorbedadequately. Thus, on continued secretion, pressure increases greatly,causing the ventricles to swell or expand. As expansion occurs the wallmaterial becomes thinned. Expansion occurs at the expense of brainsubstance, and fluids. Thus, in essence, the head becomes a box, closedsave for incoming material.

Previous attempts to relieve the extreme pressures and return suchcerebr-o-spinal fluid to the circulation have been fraught with numerousdifliculties. For example, flushing of such earlier devices has-proveddiflicult or frequently impossible, and the cardiac portion has not beenpermitted to lengthen with normal growth of the patient.

Thus, this invention has as its purpose the permitting of relieving ofincreased intra-cranialpressure by reintroducing cerebro-spinal fluidinto the vascular system.

A further object is the provision of a device which may longitudinallyextend so as to permit continuous utilization in a growing human.

Yet another object is the provision of means whereby the ventricular endmay be flushed.

These and still other objects and benefits will become "ice apparent onconsidering the following appended description and drawings in which:

FIGURE 1 is a schematic representation of the relative positioning ofthe shunt ventricular and atrial ends, pump and telescoping portions;

FIGURE 2 is a section through a skull showing positioning of the pumpmechanism and ventricular shunt relative thereto;

FIGURE 3 is an elevation of the pump mechanisms and connections thereto;

FIGURE 4 is a section through one end of the ventricular-atrial conduit.

FIGURE 5 is an enlarged elevation of the end of the ventricular portionof the shunt;

FIGURE 6 is an elevation of the telescoping portion and atrial end ofthe shunt;

FIGURE 7 is an end view of the shunt atrial end, taken along lines 6-6of FIGURE 5, and

FIGURE 7a is a section taken along lines 7a7a of FIGURE 7; and

FIGURE 8 is a section showing the placement of the shunt atrial endrelative to the superior vena cava.

Looking first at FIG. 1, for an overall view of the operation of thedevice, the venticular end of a shunt device is positioned within acranial ventricle. Said shunt ventricular end is connected to a pumpmechanism, later described, which may be inserted under the scalp. Saidpump leads subcutaneously to a telescoping section of a conduit, andthereafter to the atrial end of a shunt, which atrial end is positionedwithin the atrium of the heart. Said atrial end may be inserted in thejugular vein, through an incision therein, pass therethrough and beprevented from being dislodged from the atrium through or to thesuperior vena cava by reason of projections near the terminal end ofsaid atrial end.

Look now at FIGURE 2 which depicts the pump and the ventricular portionof the shunt. Said shunt refers to the conduits from either end of thepump. The skull of a person is indicated by the numeral 10, and thescalp by 12. An aperture is shown by 14, which may be a burr hole oreven a perforator opening which is substantially smaller.

A ventricular shunt 20, which consists generally of thin flexible hollowconduit, preferably of silicone rubber, has one end 21 inserted within acranial ventricle, which ventricle is under excessive pressure due tothe buildup of cerebro-spinal fluid. Said one end possesses a number ofperforations, with the perforations closely bunched and arrangedpreferably with each grouping being rotated 90 from the adjacentgrouping and vertically spaced therefrom, as indicated by groups 22, 23,and 24, respectively (FIG. 5).

The other end 25 may pass through said skull opening 14, to be joined byconnector 30, to the ventricular end 41, of pump 40. Said connector maybe made of polyethylene, silicone rubber, nylon or other suitablematerial, and would have an aperture therethrough, communicating bothwith the ventricular shunt and with conduit-like end 41 of said pump.

The pump 40, actually would perform as a dual pumping mechanism in the.following manner. A flexible base portion 43 possesses suture holes 44for aflixing said base to periosteum of skull 10. Spaced toward oppositeends of said base are hemisphere-like bubble portions 50 and 60, whichdefine chambers 51 and 61, respectively, between said bubbles and saidbase. Actually, said bubbles serve as individual pumps in that each maybe compressed so as to eject fluids present within their respectivecavities outwardly thereof. Said conduit end 41 is shown to communicateboth with ventricular pump 50 and with ventricular shunt 20, by virtueof connector 30. Also, pump 50 communicates with atrial pump 60 byvirtue of ventricular-atrial conduit 70. The atrial end 71 of saidconduit terminates within chamber 61 of pump 60-. Said atrial end mayhave a slit 72 formed therein which, in the absence of suflicientpressure against the adjacent walls, would normally be closed. Thus saidconduit and slit would function as a one way valve preventing fluidsfrom returning from chamber '61 to chamber 51, i.e., from the atrialshunt through the ventricular shunt thence back into the ventricle.

Atrial pump 60 is linked by conduit '81,.by virtue of connector 89,similar to member 30', to the upper member 91 of atrial shunt 90 andcommunicates therewith by virtue of said conduit, connector and shuntbeing cylindrically conformed.

Said upper portion 91 will have a larger internal diameter than, andtelescopingly receive lower portion 92, both portions consisting oftubing, preferably, again of silicone rubber. The telescoping portion ofmember 92 may be prevented from sticking by properly coating members 91and 92.

FIGURES 6, 7, 7a and 8 depict said lower portion of the atrial shunt.The lower or atrial end 93 of member 92, includes one or more slits 94,again functioning as a one-way valve. Positioned closely adjacentthereto are a plurality of slightly upwardly directed, wing-likeprojections 100. Preferably there are three such projections spacedradially 120 degrees apart around the periphery of the end 93 of theatrial shunt.

It woud be beneficial for the device to be substantially treated with abarium-containing substance so that on X- rays being taken, theexactlocation of all the parts thereof may be determined.

In actual use, ventricular shunt 20' would be inserted through cranialperforation 14 into a cranial ventricle, the brain being underconsiderable internal pressure. Cerebrospinal fluid would pass throughapertures 22, 23 and 24 into the interior of ventricular shunt 20,therethrough, into cavity 51 of pump 50, thence through conduit 70, outone-way valve 72 into chamber 61 of pump 60. Said pump 60 may, bypressing down on the adjacent scalp, and thereby compressing the pump60, cause such fluids to pass downwardly through conduit 81, connector89 and into the upper member 91 of atrial shunt 90, from Where it wouldpass through the atrial end 92 of said atrial shunt, out one-way valve94, into the atrium from which location said fluids may eventually beabsorbed into the blood system. Pressure on pump 50 would normally havethe same effect. Normally, in the absence of obstructions or occlusions,said pumps would not need to be utilized, in that said fluids wouldfollow the described route without needing assistance.

Normally the linkage from the pumping mechanism to the atrial end of theatrial shunt may be inserted underneath the skin. The lower member 92 ofsaid atrial shunt 90 would be inserted within the jugular vein andcourse through the superior vena cava, pass downwardly therethrough intothe atrium. By virtue of projections 100', which may readily bendupwardly, so as to permit downward passage through said superior venacava 110, said atrial end of said atrial shunt, may not return upwardlythrough vein 110, in that said projections 1 00 would rest adjacentatrial wall 120. This would tend to prevent scarring of the superiorvena cava wall as well as thrombosis which might occur should member 92be pulled back within vein 110, and be bound to the wall thereof by amembrane or clot. Even should said atrial end be pulled back within vein110, said projections 100* would keep said atrial end centered in thestream of blood flowing through said vein, keeping the device operative.Positioning of atrial end 93 is permitted, even in growing children byvirtue of the telescoping nature of members 91 and 92.

A further advantage permitted by this device is the flushing of theventricular end of the shunt. Inasmuch as conduit 70 has a one-way valve72 at one end, if pump 60 is depressed so as to close said valve, thenpressure on valve 50 will tend to force fluids contained in cavity 51and the ventricular shunt 20 back through the perforations in end 21.Thus, stoppages resulting from occlusion of the ventricular end, perhapsbits of brain matter, debris or clumped leukocytes may be overcome.

Although only a single embodiment of this invention has been describedit should be apparent that numerous modifications would be possible byone skilled in the art without departing from the spirit of theinvention. The scope of which is.intended to be limited only by thefollowing appended claims.

What is claimed is: 1. In a surgically implantable device for relievingexcess pressure within the brain comprising a first fluid conduit meansadapted for introduction of at least a portion thereof into a brainventricle, a second fluid conduit means for fluid outlet, a pumpingdevice positioned between said first and second conduit means andinterconnecting the same, and a one-way valve positioned in the systemto prevent fluid back-flow into the brain, the improvement whichcomprises:

said pumping device comprising a pair of hemispherelike, bubble-shaped,thin-walled resilient chamber portions positioned in spaced relationshipon a substantially flat, flexible base member, said base member definingthe lower boundary of each of said chamber portions, each portion beingadjacent to one of said conduits and intercommunicating therewith,

said bubble-shaped chamber portions being interconnected by thirdconduit means including a one-way valve whereby when said pumping deviceis manipulated, the first conduit can be flushed to clear it ofobstructions.

2. The improvement as defined in claim 1 wherein said third conduitmeans terminates within said chamber adjacent to said secondconduitmeans.

3. The improvement as defined in claim 2 wherein said one-way valve insaid third conduit means is provided with a slit which acts as a one-wayvalve.

3 4. The improvement as defined in claim 1 wherein: the terminal portionof said second conduit means, which is opposite the end to which saidpumping device is connected, is provided with a plurality of wing-like,flexible projections adapted to rest against blood vessel walls of thepatient and center the conduit in the flow of the blood.

5. The improvement as defined in claim 1 wherein: said flexible basemember is provided with means for attachment of sutures thereto.

References Cited UNITED STATES PATENTS 2,616,429 11/ 1952 MerenlenderI28350 2,969,066 1/1961 Holter et al 128350 3,020,913 2/1962 Heyer128350 3,111,125 11/1963 Schulte 128-350 3,108,595 10/1963 Overment128-350 3,233,610 2/1966 Wade 128-350 3,288,142 11/1966 Hakim 128-35OOTHER REFERENCES Lancet: vol. 2 (63), No. 7315, Nov. 9, 1963, pp. 983-984.

Rickham: Brit. Med. Jour., July 1964, p. 173.

Hakim Valve System for Ventriculo-Atriostomy, Cords Corp. Publicationdated Oct. 5, 1965, pp. 3 and 6- 8 relied on.

DALTON L. TRULUCK, Primary Examiner

